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Objective: The aim is to study the effects of metformin on the expression of 70 kDa ribosomal protein S6 kinase (P70S6k), insulin receptor substrate 1 (IRS-1), and IRS-1Ser307 phosphorylation in human luteinized granulosa cells. Methods: Granulosa cells in the experimental group were cultured in M199 medium containing 0.1 mmol/L metformin for 24 h and those in control group were cultured in M199 medium. The expression levels of P70S6k and IRS-1 mRNA were detected by reverse-transcriptiom polymerase chain reaction (RT-PCR) and real-time PCR. P70S6k, IRS-1, p-ser307-IRS-1, and p-thr389-P70S6k protein expression levels were detected by immunofluorescence and western blotting. Results: P70S6k mRNA level was higher and IRS-1 was significantly lower in the experimental group than those in the control group. IRS-1 and p-ser307-IRS-1 were expressed in cell plasma, and P70S6k and p-thr389-P70S6k were expressed in cell nucleus. The results of Western blot analysis indicated that the expression levels of P70S6k, p-thr389-P70S6k, IRS-1, and p-ser307-IRS-1 proteins had significant difference between the experimental group and the control group. Compared to the control group, the relative intensity illustrated that the expression levels of P70S6K and p-thr389-P70S6k significantly increased in the experimental group; however, those of IRS-1 and p-ser307-IRS-1 proteins significantly decreased. Conclusion: Metformin can inhibit the P70S6k mRNA and protein expression levels in the granulosa cells and improve insulin sensitivity by regulating IRS-1 expression through Akt/P70S6k/IRS-1-dependent pathway.

The fringe -reflection technology has been widely applied in the fields of industrial inspection and measurements. In the present study, three-step phase-shifting is developed using the color fringe-reflection approach to inspect a work-piece surface with rotational symmetry characteristics, and an improved experiment is proposed. In addition, by combining Robert gradient with fringe modulation, a new quality weight, referred to as ‘Modulation-Robert gradient variance’ (MRGV), is proposed for quality-guiding the phase-unwrapping (PU) algorithm. In comparison to the traditional quality weights, MRGV presented higher noise immunity and lower PU error in the root mean square (RMS). In addition, in terms of defect detection, MRGV performed better than the other weights. Finally, after MRGV-guided PU conduction, the proposed experiment method is used in combination with an improved Southwell integration algorithm to realize the 3D reconstruction. The reconstruction error is approximately 3.09% lower than that presented by certain other methods. Furthermore, the results indicated that the combination of the proposed method and the new quality weight could effectively detect the defects and offer an accurate measurement of a rotationally symmetrical surface to a certain extent.

With the development of regenerative medicine, a variety of mesenchymal stem cells (MSCs) are increasingly considered for the treatment of premature ovarian failure (POF). Reportedly, bone marrow-derived MSCs (BMSCs) improve the ovarian reserve, which mainly depends on homing and paracrine activities. Furthermore, paracrine factors secreted by these stem cells play an important role in ovarian recovery. Relevant studies indicate that BMSC transplantation has some positive effects on the treatment of POF in animals, but BMSCs are not widely applied in clinical therapy. Clinical trials are ongoing despite the fact that several patients experiencing BMSC transplantation recover their normal menstrual cycles and even give birth to babies. In this review, we discuss the possible therapeutic mechanisms of BMSCs for POF, migration, antiapoptosis, antifibrosis, angiogenesis, anti-inflammation, immunoregulation, and oxidative stress, which provide the theoretical basis for further study and clinical therapy.

The importance of protein tyrosine phosphatases (PTPs) in the regulation of cellular signalling is well established. Malfunction of PTP activity is also known to be associated with cancer, metabolic syndromes and autoimmune disorders, as well as neurodegenerative and infectious diseases. However, a detailed understanding of the roles played by the PTPs in normal physiology and in pathogenic conditions has been hampered by the absence of PTP-specific small molecule agents. In addition, the therapeutic benefits of modulating this target class are underexplored as a result of a lack of suitable chemical probes. Potent and specific PTP inhibitors could significantly facilitate functional analysis of the PTPs in complex cellular signal transduction pathways and may constitute valuable therapeutics in the treatment of several human diseases. We highlight the current challenges to and opportunities for developing PTP-specific small molecule agents. We also review available selective small molecule inhibitors developed for a number of PTPs, including PTP1B, TC-PTP, SHP2, lymphoid-specific tyrosine phosphatase, haematopoietic protein tyrosine phosphatase, CD45, PTPβ, PTPγ, PTPRO, Vaccinia H1-related phosphatase, mitogen-activated protein kinase phosphatase-1, mitogen-activated protein kinase phosphatase-3, Cdc25, YopH, mPTPA and mPTPB.